Thank you for contacting Illinois Extension Forestry. Please note that most tree insect/disease concerns require on-site inspection and assessment by a qualified professional (i.e., horticulturist, certified arborist, urban forester, entomologist, or plant pathologist).
Therefore, the most expedient way to address your ‘tree’ insect and disease questions and concerns are listed below:
1) Visit your local county Univ. of Illinois Extension office (bring photos, insects, or plant samples) and ask to speak with a horticulturist or Master Gardener
2) Visit the University of Illinois Extension’s Distance Diagnosis Website:
3) Contact a local certified arborist for an on-site inspection and assessment of the tree(s) in question. A listing of certified arborists is found on the Illinois Arborist Association Website:
4) Submit a specimen sample of your affected tree(s) to either the University of Illinois Plant Clinic http://plantclinic.cropsci.illinois.edu/ or to The Morton Arboretum Plant Clinic http://www.mortonarb.org/plant-clinic.html
In addition, here are several tips to assist you in your efforts: (a) Determine the species, age, size, history, and general condition of the affected tree; (b) Take digital photographs of the tree and its adjacent surroundings; (c) Take digital photographs of the affected leaves, trunk, branches, fruit, etc., and (d) Write down any notes regarding nearby construction projects, flood or drought events, storm damage or other weather related phenomena, etc. This information will prove invaluable to the individual assisting you.